Several tritylodontid taxa have been reported from the Upper Jurassic of the Wucaiwan area in the Junggar Basin of Xinjiang,northwestern China,including Yuanotherium minor.The original study described the partially pr...Several tritylodontid taxa have been reported from the Upper Jurassic of the Wucaiwan area in the Junggar Basin of Xinjiang,northwestern China,including Yuanotherium minor.The original study described the partially preserved postcanine teeth in the middle of the left upper maxilla.After detailed re-examination of the specimen and by CT scanning,3D reconstruction,and scanning electron microscopy observations,we provided a more detailed description of the osteology,neurosensory,and tooth wear pattern for all the bones preserved in this specimen and clarified some characters.Based on new information about the cusp wear pattern,the chewing movement pattern of the dentition and detailed cusp morphology,we discussed the cuspal homology of upper cheek teeth of tritylodontids and postulate a standardized method for cusp identification.We hypothesize that the unique maxilla characteristics furnish the evidence for transitional stages about the evolution of the upper jaw-palate structure in tritylodontids.展开更多
The origin of birds from theropod dinosaurs,by any measures,is the most eye-catching evolutionary transition in the history of life,which encompasses numerous extensive morphological and biological changes.Compared to...The origin of birds from theropod dinosaurs,by any measures,is the most eye-catching evolutionary transition in the history of life,which encompasses numerous extensive morphological and biological changes.Compared to postcranium,little progress has been made regarding the evolutionary assemblage of the birds’skull,because of few detailed early records of cranial materials of stem lineages.Anchiornis is the oldest known record of the Paraves(~160 Ma),the most inclusive clade that contains all living birds but not Caudipteryx or Epidexipteryx.With hundreds of known specimens,Anchiornis constitutes an ideal taxon for investigating morphological modifications across the theropod-bird transition,but its cranial morphology remains enigmatic.Here we present in-depth description of the cranial morphology of Anchiornis based on three-dimensional reconstruction of a well-preserved specimen,including elements from the temporal and palatal regions that are poorly recognized previously.Our study shows that Anchiornis retains the plesiomorphic dinosaurian condition in having a diapsid akinetic skull.The mixture of cranial characters,shared with dromaeosaurids,troodontids,and stemward avialans,present in Anchiornis demonstrates the complex history of early avialan cranial evolution.展开更多
In 2015,the discovery of mammalian fossils,paleolithic artifacts,and burned bones in the Maoershan Cave of the Guilin Basin,northeastern Guangxi,indicated that it is a late Middle Pleistocene Paleolithic site.In 2021,...In 2015,the discovery of mammalian fossils,paleolithic artifacts,and burned bones in the Maoershan Cave of the Guilin Basin,northeastern Guangxi,indicated that it is a late Middle Pleistocene Paleolithic site.In 2021,stratigraphic sectioning and the systematic screening of small mammal sand samples were conducted.This paper presents a comprehensive account of the new material of the fruit bat Rousettus leschenaultii,accompanied by a concise overview of the non-volant micromammals that coexisted with it in the Quaternary sediments of the Maoershan Cave.This finding marks the second occurrence of fruit bat fossils in China,contributing to our understanding of the dental morphology and past geographical distribution of Rousettus.The micromammalian assemblage of the Maoershan Cave is composed of 3 orders,9 families,26 genera,and 30 species,and exhibits notable similarities with those of the late Middle Pleistocene Yumi Cave,Xinglong Cave,Yanhui Cave,Mawokou Cave,Zhongliangshan,and Chuan Cave faunas.The biochronology of the micromammalian assemblage from the Maoershan Cave has been determined to be consistent with the late Middle Pleistocene,providing a new assemblage in the Pleistocene mammalian faunal sequence in southern China.The presence of abundant oriental forested elements indicates that the Guilin Basin used to be a humid and warm subtropical forest paleoenvironment similar to the contemporary environment during the late Middle Pleistocene.展开更多
This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eg...This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eggs can be referred to Elongatoolithidae.The gradual boundary between the cone and the column layers as well as the relative thin eggshell(less than 1 mm)indicates its affinity within Elongatoolithus.The eggs are identified as Elongatoolithus oosp.,as they were severely compressed and experienced erosion on both inner and outer surfaces.The discovery of egg fossil in the Hefei Basin offers evidence for stratum comparison in this region and supplements the diversity of egg fossils in Anhui.Meanwhile,this discovery also enriches the paleogeographic distribution of elongatoolithids.展开更多
Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olen...Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olenekian,Early Triassic)marine deposits of Jurong,Jiangsu and Chaohu,Anhui,China.This new discovery documents the third and youngest species of Teffichthys,which is slightly younger than the Dienerian(Induan)T.elegans from Guizhou and the early Smithian T.madagascariensis from Madagascar.The new species shows diagnostic features of Teffichthys(presence of a spiracular,38-41 lateral line scales,and no more than three epaxial rays in the caudal fin)but differs from T.madagascariensis and T.elegans in some autapomorphies(e.g.,a horizontal opercle/subopercle contact and smooth scales with a nearly straight posterior margin).The diagnostic features for the genus Teffichthys and the family Perleididae are emended based on detailed comparisons of the new taxon with other perleidids.The phylogenetic relationships of perleidids with other stem neopterygians are discussed using a cladistic approach,and the results provide new insights into the phylogeny and classification of main stem neopterygian clades.展开更多
Stegolophodon is an age-informative genus of mammals that had a widespread distribution during the Neogene.This paper reports the discovery of Stegolophodon fossils from the Middle Miocene lower Fotan Formation at the...Stegolophodon is an age-informative genus of mammals that had a widespread distribution during the Neogene.This paper reports the discovery of Stegolophodon fossils from the Middle Miocene lower Fotan Formation at the Zhangpu locality,Fujian Province,China.This discovery represents the first evidence of Neogene proboscidean fossils in southeastern China.The newly found molar materials have low tooth crowns,very straight lophs/lophids,and an indistinct median sulcus.The mesoconelets and posterior cingulum are well-developed,while the second posterior pretrite central conule is significantly reduced.These specimens closely resemble Stegolophodon pseudolatidens in cheek tooth morphology,and can thus be attributed to the same species.This discovery fills a gap in the fossil record of large mammals in this region during the Neogene and provides valuable insights into the evolution of proboscideans and paleoenvironments.展开更多
Monsoon has an important impact on the development of vegetation that subsequently has significant influence on the evolution of plant consumers.The diversities of forest dwellers or herbivores follow the evolution of...Monsoon has an important impact on the development of vegetation that subsequently has significant influence on the evolution of plant consumers.The diversities of forest dwellers or herbivores follow the evolution of the vegetation,and it is therefore possible to take such diversities as forest or vegetation dynamic proxies.The present work selected 36 Pleistocene faunas of large mammals from monsoon-dominated provinces in China as materials and calculated the diversities of forest dwellers and herbivores with different approaches,as well as the consensus gradient coefficients of all the selected faunas in different flora regionalized subkingdoms.The results show that with the evolution and transitions of the East Asian summer and winter monsoon intensities,the forest vitality decreased while steppe vitality increased gradually in a fluctuated way from the Early Pleistocene to the Late Pleistocene,especially in the provinces north of the Qinling-Huaihe Line.The analyses of such diversities of the faunas can help to determine the forest dynamic proxies.Moreover,the correlation of such proxies to loess-paleosol sequences and marine isotope stages can in turn help to improve the accuracy of dating fauna ages and paleoenvironment reconstruction.展开更多
The Upper Cretaceous of Tantou Basin in western Henan has yielded many vertebrate fossils,which are featured by several non-avian dinosaurs.Meanwhile,studies on their eggs were yet inadequate though many eggshells hav...The Upper Cretaceous of Tantou Basin in western Henan has yielded many vertebrate fossils,which are featured by several non-avian dinosaurs.Meanwhile,studies on their eggs were yet inadequate though many eggshells have been reported.The newly discovered material 41HⅤ0199 was excavated from the Upper Cretaceous Qiupa Formation in 2021.The block preserves eight complete eggs arranged in two partial rings that form a partial clutch,and there are some scattered eggshells preserved closely with the block,showing a concave-up to concave-down ratio of 54.5:45.5,which indicates that the scattered eggshells come from the clutch and the clutch had been partially broken before it was buried.Based on morphological and microstructural characteristics,the eggs and eggshells can be assigned to Macroolithus yaotunensis(Elongatoolithidae),an oospecies known to be related to oviraptorids,which leads Yulong mini to be its probable producer.Besides,some eggshells show microstructural signs indicating egg retention,which marks the second example of egg retention in the oofamily Elongatoolithidae.展开更多
A controversial taxon,Hipparion plocodus,is reviewed in the present study.Hi.plocodus has been confirmed to be a valid species with definite diagnostic characteristics,represented by cranial specimens from Baode,Shanx...A controversial taxon,Hipparion plocodus,is reviewed in the present study.Hi.plocodus has been confirmed to be a valid species with definite diagnostic characteristics,represented by cranial specimens from Baode,Shanxi Province.The phylogenetic analysis performed in the present study,with a new matrix,shows that Hi.plocodus forms a monophyletic group with a European species,Hippotherium malpassii.Actually,no close relationship between so-called Hm.malpassii and the genus Hippotherium has been identified,and the record of stratigraphic range of this genus in late stage of Late Miocene is currently absent.Herein previously Hi.plocodus and Hm.malpassii have both attributed into“Hipparion”before the discovery of better material.Evolutionary stages and correlative absolute age showed that these two species should derive independently from some primitive clade.During the late stage of the Late Miocene,the development of the Asian summer monsoon enhanced the humidity of China,with forest and wood habitats expanding considerably under this setting.As the result,one Eurasian closed-habitat lineage thus extended its range into China,which had become very suited for it,give rise to“Hi.”plocodus.展开更多
Here we report a left cheek plate of Psarolepis,a postparietal shield of Youngolepis,a skull of Diabolepis,and a scale of Styloichthys from the Lianhuashan and Nahkaoling formations(Lochkovian,Lower Devonian)of Nannin...Here we report a left cheek plate of Psarolepis,a postparietal shield of Youngolepis,a skull of Diabolepis,and a scale of Styloichthys from the Lianhuashan and Nahkaoling formations(Lochkovian,Lower Devonian)of Nanning,Guangxi.This marks the first report of Diabolepis and Styloichthys beside Qujing,Yunnan,and the latest occurrence of Psarolepis to date.The fossil community displays significant similarities to the Xujiachong Assemblage,and provides new data for the Lower Devonian stratigraphic correlation between southwestern China and northern Vietnam.Given the latest dating constraint based on the conodont evidence,we regard that the Xujiachong Assemblage has a much longer range than previously supposed,extending from the latest Lochkovian to the end of Pragian.We propose that the transition of the Nahkaoling and Lianhuashan formations in Nanning might correspond to the Guijiatun Formation in Qujing.The relatively large size of fish individuals from Guangxi is probably attributed to the increase in the oxygen content of the ocean.展开更多
Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocen...Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin in North China provide new insight into the evolution of its kind in North China.The new materials include partial skulls and mandibles of males,and most of their teeth were preserved in situ.The specimens can be referred to the species Sus lydekkeri,which is the only species of Sus found in North China from the Early Pleistocene.The fossils of the once reported Pleistocene species“Potamochoerus chinhsienensis”should also be provisionally included in the species S.lydekkeri according to its form and size,which at least now excludes it from Potamochoerus.The species S.lydekkeri is very close to the extant species S.scrofa,and even was combined into the latter as a chronological subspecies by some authors,while its larger size,prominent preorbital fossa,backwardly positioned infraorbital foramen,frequently appearing verrucosic type(at least the intermediate type of the male lower canine),and simple crown structures support its validness as an independent species.The Early Pleistocene forms are characterized by a larger size,lower L/W ratio of cheekteeth,both upper and lower M3s having no more than three lobes,and the male lower canine is exclusively of a verrucosic type.Suid fossils are a very good indicator of paleoenvironments and paleoclimate.Both the northern and the southern faunas in China contain suid fossils throughout the Pleistocene Epoch,while the southern fauna has prominently more diversified taxa and more abundant fossil collections;whether that is caused by different origins or by environmental modifications is still not clear.展开更多
Pantodonta was one of the first groups of eutherians to evolve at the beginning of Cenozoic era,including the largest herbivores at that time.Pantodonta shows considerable diversity during the Paleocene and Eocene,wit...Pantodonta was one of the first groups of eutherians to evolve at the beginning of Cenozoic era,including the largest herbivores at that time.Pantodonta shows considerable diversity during the Paleocene and Eocene,with most of the species having been discovered in Asia and North America.Here,we report on a new pantodont,represented by lower jaws with well-preserved dentition,discovered from the Middle Paleocene Nongshan Formation of the Nanxiong Basin,Guangdong Province,China.Its unique dental and mandibular characteristics distinguish it well from any known Asian pantodont,but are quite consistent with North American taxa,especially Pantolambda and Titanoides.The new specimen is identified as Nanxiongilambda yei gen.et sp.nov.,characterized by the combination of the following morphological features:thick and robust mandible with a conspicuous anteroexternal flange,high positioned condyloid process,posteriorly protruding angular process,robust but not elongated lower canines,double-rooted p1,small but distinct talonids on posterior lower premolars,talonids nearly as wide as trigonids on lower molars,and m3 with a well-developed hypoconulid and a distinct entoconid.The new discovery marks the first record of a pantolambdid pantodont outside of North America,suggesting a broader geographical distribution and intercontinental dispersal of this clade during the Paleocene.Considering the more primitive Pantolambda only found from Torrejonian to early Tiffanian NALMA(equivalent to middle-late Shanghuan to early Nongshanian ALMA),which is slightly earlier than Nanxiongilambda(early Nongshanian ALMA),pantolambdids have likely undergone a particular wave of migration from North America to Asia during the Early-Middle Paleocene.Previous researches have suggested that pantodonts had dispersed only from Asia to North America during the Early Paleocene,but our new specimen indicates the biotic dispersal may have occurred in the opposite direction.The new specimen also contributes to the renewal of the evolutionary history of pantodonts and provides further insights into the migration and dispersal of Paleocene mammals.展开更多
Within the dicynodont genus Turfanodon,there are two recognized species,T.bogdaensis and T.jiufengensis.Both species are known by relatively complete cranial materials,but the mandibles and most postcranial bones have...Within the dicynodont genus Turfanodon,there are two recognized species,T.bogdaensis and T.jiufengensis.Both species are known by relatively complete cranial materials,but the mandibles and most postcranial bones have been described only for T.jiufengensis.This paper reports new dicynodont specimens from Turpan,Xinjiang,referring them to T.bogdaensis.They can clearly be differentiated from T.jiufengensis by the flatter lateral surface of the snout region,a prominent swelling on the lateral dentary shelf,and the rounded femoral head.The diagnosis of Turfanodon is revised.The combination of a flat circumorbital rim,posterior portion of anterior pterygoid rami with converging ventral ridges,and a possible autapomorphy,a deep notch on scapula forming procoracoid foramen,are confirmed.It also differentiated from all dicynodonts other than Myosaurus,Kembawacela and Lystrosaurus by having accessory ridges lateral to the median palatal ridge.展开更多
The early Silurian Chongqing Lagerstätte(middle Telychian)yields exceptionally preserved articulated jawless and jawed fishes.Here,we describe a new eugaleaspiform(Galeaspida,jawless stem-Gnathostomata),Miaojiaas...The early Silurian Chongqing Lagerstätte(middle Telychian)yields exceptionally preserved articulated jawless and jawed fishes.Here,we describe a new eugaleaspiform(Galeaspida,jawless stem-Gnathostomata),Miaojiaaspis dichotomus gen.et sp.nov.,from the Chongqing Lagerstätte in Xiushan,Chongqing,China.The new form resembles Tujiaaspis vividus in the short medial dorsal canal,and the presence of the branching ends of the lateral transverse canal.They differ in that T.vividus has highly developed subordinate branches of the sensory canals that form a reticulate sensory canal system,and the median dorsal opening is more elongated.Our phylogenetic analysis recovers M.dichotomus and T.vividus as a monophyletic clade(Tujiaaspidae fam.nov.),which is supported by two synapomorphies:the short medial dorsal canal,and the branching ends of the lateral transverse canal.Tujiaaspidae forms a trichotomy with Shuyuidae and a clade comprising Anjiaspis,Sinogaleaspidae,Yongdongaspidae,and the‘eugaleaspid cluster’.The sensory canal patterns in galeaspids are compared to show the transformation sequence of the sensory canal system in Eugaleaspiformes.展开更多
X-ray computed tomography(CT)has been an important technology in paleontology for several decades.It helps researchers to acquire detailed anatomical structures of fossils non-destructively.Despite its widespread appl...X-ray computed tomography(CT)has been an important technology in paleontology for several decades.It helps researchers to acquire detailed anatomical structures of fossils non-destructively.Despite its widespread application,developing an efficient and user-friendly method for segmenting CT data continues to be a formidable challenge in the field.Most CT data segmentation software operates on 2D interfaces,which limits flexibility for real-time adjustments in 3D segmentation.Here,we introduce Curves Mode in Drishti Paint 3.2,an open-source tool for CT data segmentation.Drishti Paint 3.2 allows users to manually or semi-automatically segment the CT data in both 2D and 3D environments,providing a novel solution for revisualizing CT data in paleontological studies.展开更多
The Tyrannosauridae,which is characterized by specialized pachydont dentition and putative bone-cracking predatory strategies,is one of the most extensively studied theropod lineages.Although tooth replacement pattern...The Tyrannosauridae,which is characterized by specialized pachydont dentition and putative bone-cracking predatory strategies,is one of the most extensively studied theropod lineages.Although tooth replacement patterns,crucial for understanding feeding behaviors,have been thoroughly studied in this group,studies on non-tyrannosaurid tyrannosauroids are relatively scarce.This study utilizes high-resolution CT data to investigate the tooth replacement pattern in two specimens of Guanlong wucaii,a Late Jurassic tyrannosauroid,and provides insights into the evolution of tooth replacement across Tyrannosauroidea.Second-generation replacement teeth,a rarity observed mainly in giant predatory theropods(e.g.some tyrannosaurids),were detected in the dentary dentition of the juvenile Guanlong.Zahnreihen reconstructions display a consistent cephalad alternating tooth replacement pattern in the maxilla and the dentary of both of the examined individuals,with Z-spacing values exceeding 2.0.As Guanlong grows,the Z-spacing value in the maxillary dentition increases,resembling the ontogenetic changes documented in the Tyrannosauridae.Additionally,like Tarbosaurus,Guanlong also displays a discontinuity between the tooth replacement waves at the premaxilla-maxilla boundary.This study thus demonstrates that some tyrannosaurid-like tooth replacement patterns were acquired before the origin of the Tyrannosauridae.展开更多
A relatively well-preserved rodent fossil,including its incisors,cheek teeth,and postcranial skeleton,was collected from the Baiyin Obo in Siziwang Banner,Nei Mongol.A multifaceted research approach was undertaken in ...A relatively well-preserved rodent fossil,including its incisors,cheek teeth,and postcranial skeleton,was collected from the Baiyin Obo in Siziwang Banner,Nei Mongol.A multifaceted research approach was undertaken in this study to conduct a comprehensive analysis on the newly discovered specimen.Based on a morphological comparison,the new specimen was identified as Hulgana cf.H.ertnia within the Ischyromyidae family.Incisive enamel microstructure analysis revealed the typical pauciserial enamel structure of Hulgana.Bone histological analysis indicates that the specimen represents a juvenile individual,which is consistent with the ontogenetic stage indicated by dental developmental stage and wear pattern.The application of geometric morphometrics to the calcaneus and bone histology of the femur and phalanx further substantiates the taxonomic classification of Hulgana as a terrestrial and cursorial rodent,exhibiting a degree of fossorial ability.This classification is analogous to that of certain extant cricetids and ground squirrels.展开更多
文摘Several tritylodontid taxa have been reported from the Upper Jurassic of the Wucaiwan area in the Junggar Basin of Xinjiang,northwestern China,including Yuanotherium minor.The original study described the partially preserved postcanine teeth in the middle of the left upper maxilla.After detailed re-examination of the specimen and by CT scanning,3D reconstruction,and scanning electron microscopy observations,we provided a more detailed description of the osteology,neurosensory,and tooth wear pattern for all the bones preserved in this specimen and clarified some characters.Based on new information about the cusp wear pattern,the chewing movement pattern of the dentition and detailed cusp morphology,we discussed the cuspal homology of upper cheek teeth of tritylodontids and postulate a standardized method for cusp identification.We hypothesize that the unique maxilla characteristics furnish the evidence for transitional stages about the evolution of the upper jaw-palate structure in tritylodontids.
文摘The origin of birds from theropod dinosaurs,by any measures,is the most eye-catching evolutionary transition in the history of life,which encompasses numerous extensive morphological and biological changes.Compared to postcranium,little progress has been made regarding the evolutionary assemblage of the birds’skull,because of few detailed early records of cranial materials of stem lineages.Anchiornis is the oldest known record of the Paraves(~160 Ma),the most inclusive clade that contains all living birds but not Caudipteryx or Epidexipteryx.With hundreds of known specimens,Anchiornis constitutes an ideal taxon for investigating morphological modifications across the theropod-bird transition,but its cranial morphology remains enigmatic.Here we present in-depth description of the cranial morphology of Anchiornis based on three-dimensional reconstruction of a well-preserved specimen,including elements from the temporal and palatal regions that are poorly recognized previously.Our study shows that Anchiornis retains the plesiomorphic dinosaurian condition in having a diapsid akinetic skull.The mixture of cranial characters,shared with dromaeosaurids,troodontids,and stemward avialans,present in Anchiornis demonstrates the complex history of early avialan cranial evolution.
文摘In 2015,the discovery of mammalian fossils,paleolithic artifacts,and burned bones in the Maoershan Cave of the Guilin Basin,northeastern Guangxi,indicated that it is a late Middle Pleistocene Paleolithic site.In 2021,stratigraphic sectioning and the systematic screening of small mammal sand samples were conducted.This paper presents a comprehensive account of the new material of the fruit bat Rousettus leschenaultii,accompanied by a concise overview of the non-volant micromammals that coexisted with it in the Quaternary sediments of the Maoershan Cave.This finding marks the second occurrence of fruit bat fossils in China,contributing to our understanding of the dental morphology and past geographical distribution of Rousettus.The micromammalian assemblage of the Maoershan Cave is composed of 3 orders,9 families,26 genera,and 30 species,and exhibits notable similarities with those of the late Middle Pleistocene Yumi Cave,Xinglong Cave,Yanhui Cave,Mawokou Cave,Zhongliangshan,and Chuan Cave faunas.The biochronology of the micromammalian assemblage from the Maoershan Cave has been determined to be consistent with the late Middle Pleistocene,providing a new assemblage in the Pleistocene mammalian faunal sequence in southern China.The presence of abundant oriental forested elements indicates that the Guilin Basin used to be a humid and warm subtropical forest paleoenvironment similar to the contemporary environment during the late Middle Pleistocene.
文摘This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eggs can be referred to Elongatoolithidae.The gradual boundary between the cone and the column layers as well as the relative thin eggshell(less than 1 mm)indicates its affinity within Elongatoolithus.The eggs are identified as Elongatoolithus oosp.,as they were severely compressed and experienced erosion on both inner and outer surfaces.The discovery of egg fossil in the Hefei Basin offers evidence for stratum comparison in this region and supplements the diversity of egg fossils in Anhui.Meanwhile,this discovery also enriches the paleogeographic distribution of elongatoolithids.
文摘Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olenekian,Early Triassic)marine deposits of Jurong,Jiangsu and Chaohu,Anhui,China.This new discovery documents the third and youngest species of Teffichthys,which is slightly younger than the Dienerian(Induan)T.elegans from Guizhou and the early Smithian T.madagascariensis from Madagascar.The new species shows diagnostic features of Teffichthys(presence of a spiracular,38-41 lateral line scales,and no more than three epaxial rays in the caudal fin)but differs from T.madagascariensis and T.elegans in some autapomorphies(e.g.,a horizontal opercle/subopercle contact and smooth scales with a nearly straight posterior margin).The diagnostic features for the genus Teffichthys and the family Perleididae are emended based on detailed comparisons of the new taxon with other perleidids.The phylogenetic relationships of perleidids with other stem neopterygians are discussed using a cladistic approach,and the results provide new insights into the phylogeny and classification of main stem neopterygian clades.
文摘Stegolophodon is an age-informative genus of mammals that had a widespread distribution during the Neogene.This paper reports the discovery of Stegolophodon fossils from the Middle Miocene lower Fotan Formation at the Zhangpu locality,Fujian Province,China.This discovery represents the first evidence of Neogene proboscidean fossils in southeastern China.The newly found molar materials have low tooth crowns,very straight lophs/lophids,and an indistinct median sulcus.The mesoconelets and posterior cingulum are well-developed,while the second posterior pretrite central conule is significantly reduced.These specimens closely resemble Stegolophodon pseudolatidens in cheek tooth morphology,and can thus be attributed to the same species.This discovery fills a gap in the fossil record of large mammals in this region during the Neogene and provides valuable insights into the evolution of proboscideans and paleoenvironments.
文摘Monsoon has an important impact on the development of vegetation that subsequently has significant influence on the evolution of plant consumers.The diversities of forest dwellers or herbivores follow the evolution of the vegetation,and it is therefore possible to take such diversities as forest or vegetation dynamic proxies.The present work selected 36 Pleistocene faunas of large mammals from monsoon-dominated provinces in China as materials and calculated the diversities of forest dwellers and herbivores with different approaches,as well as the consensus gradient coefficients of all the selected faunas in different flora regionalized subkingdoms.The results show that with the evolution and transitions of the East Asian summer and winter monsoon intensities,the forest vitality decreased while steppe vitality increased gradually in a fluctuated way from the Early Pleistocene to the Late Pleistocene,especially in the provinces north of the Qinling-Huaihe Line.The analyses of such diversities of the faunas can help to determine the forest dynamic proxies.Moreover,the correlation of such proxies to loess-paleosol sequences and marine isotope stages can in turn help to improve the accuracy of dating fauna ages and paleoenvironment reconstruction.
文摘The Upper Cretaceous of Tantou Basin in western Henan has yielded many vertebrate fossils,which are featured by several non-avian dinosaurs.Meanwhile,studies on their eggs were yet inadequate though many eggshells have been reported.The newly discovered material 41HⅤ0199 was excavated from the Upper Cretaceous Qiupa Formation in 2021.The block preserves eight complete eggs arranged in two partial rings that form a partial clutch,and there are some scattered eggshells preserved closely with the block,showing a concave-up to concave-down ratio of 54.5:45.5,which indicates that the scattered eggshells come from the clutch and the clutch had been partially broken before it was buried.Based on morphological and microstructural characteristics,the eggs and eggshells can be assigned to Macroolithus yaotunensis(Elongatoolithidae),an oospecies known to be related to oviraptorids,which leads Yulong mini to be its probable producer.Besides,some eggshells show microstructural signs indicating egg retention,which marks the second example of egg retention in the oofamily Elongatoolithidae.
文摘A controversial taxon,Hipparion plocodus,is reviewed in the present study.Hi.plocodus has been confirmed to be a valid species with definite diagnostic characteristics,represented by cranial specimens from Baode,Shanxi Province.The phylogenetic analysis performed in the present study,with a new matrix,shows that Hi.plocodus forms a monophyletic group with a European species,Hippotherium malpassii.Actually,no close relationship between so-called Hm.malpassii and the genus Hippotherium has been identified,and the record of stratigraphic range of this genus in late stage of Late Miocene is currently absent.Herein previously Hi.plocodus and Hm.malpassii have both attributed into“Hipparion”before the discovery of better material.Evolutionary stages and correlative absolute age showed that these two species should derive independently from some primitive clade.During the late stage of the Late Miocene,the development of the Asian summer monsoon enhanced the humidity of China,with forest and wood habitats expanding considerably under this setting.As the result,one Eurasian closed-habitat lineage thus extended its range into China,which had become very suited for it,give rise to“Hi.”plocodus.
文摘Here we report a left cheek plate of Psarolepis,a postparietal shield of Youngolepis,a skull of Diabolepis,and a scale of Styloichthys from the Lianhuashan and Nahkaoling formations(Lochkovian,Lower Devonian)of Nanning,Guangxi.This marks the first report of Diabolepis and Styloichthys beside Qujing,Yunnan,and the latest occurrence of Psarolepis to date.The fossil community displays significant similarities to the Xujiachong Assemblage,and provides new data for the Lower Devonian stratigraphic correlation between southwestern China and northern Vietnam.Given the latest dating constraint based on the conodont evidence,we regard that the Xujiachong Assemblage has a much longer range than previously supposed,extending from the latest Lochkovian to the end of Pragian.We propose that the transition of the Nahkaoling and Lianhuashan formations in Nanning might correspond to the Guijiatun Formation in Qujing.The relatively large size of fish individuals from Guangxi is probably attributed to the increase in the oxygen content of the ocean.
文摘Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin in North China provide new insight into the evolution of its kind in North China.The new materials include partial skulls and mandibles of males,and most of their teeth were preserved in situ.The specimens can be referred to the species Sus lydekkeri,which is the only species of Sus found in North China from the Early Pleistocene.The fossils of the once reported Pleistocene species“Potamochoerus chinhsienensis”should also be provisionally included in the species S.lydekkeri according to its form and size,which at least now excludes it from Potamochoerus.The species S.lydekkeri is very close to the extant species S.scrofa,and even was combined into the latter as a chronological subspecies by some authors,while its larger size,prominent preorbital fossa,backwardly positioned infraorbital foramen,frequently appearing verrucosic type(at least the intermediate type of the male lower canine),and simple crown structures support its validness as an independent species.The Early Pleistocene forms are characterized by a larger size,lower L/W ratio of cheekteeth,both upper and lower M3s having no more than three lobes,and the male lower canine is exclusively of a verrucosic type.Suid fossils are a very good indicator of paleoenvironments and paleoclimate.Both the northern and the southern faunas in China contain suid fossils throughout the Pleistocene Epoch,while the southern fauna has prominently more diversified taxa and more abundant fossil collections;whether that is caused by different origins or by environmental modifications is still not clear.
文摘Pantodonta was one of the first groups of eutherians to evolve at the beginning of Cenozoic era,including the largest herbivores at that time.Pantodonta shows considerable diversity during the Paleocene and Eocene,with most of the species having been discovered in Asia and North America.Here,we report on a new pantodont,represented by lower jaws with well-preserved dentition,discovered from the Middle Paleocene Nongshan Formation of the Nanxiong Basin,Guangdong Province,China.Its unique dental and mandibular characteristics distinguish it well from any known Asian pantodont,but are quite consistent with North American taxa,especially Pantolambda and Titanoides.The new specimen is identified as Nanxiongilambda yei gen.et sp.nov.,characterized by the combination of the following morphological features:thick and robust mandible with a conspicuous anteroexternal flange,high positioned condyloid process,posteriorly protruding angular process,robust but not elongated lower canines,double-rooted p1,small but distinct talonids on posterior lower premolars,talonids nearly as wide as trigonids on lower molars,and m3 with a well-developed hypoconulid and a distinct entoconid.The new discovery marks the first record of a pantolambdid pantodont outside of North America,suggesting a broader geographical distribution and intercontinental dispersal of this clade during the Paleocene.Considering the more primitive Pantolambda only found from Torrejonian to early Tiffanian NALMA(equivalent to middle-late Shanghuan to early Nongshanian ALMA),which is slightly earlier than Nanxiongilambda(early Nongshanian ALMA),pantolambdids have likely undergone a particular wave of migration from North America to Asia during the Early-Middle Paleocene.Previous researches have suggested that pantodonts had dispersed only from Asia to North America during the Early Paleocene,but our new specimen indicates the biotic dispersal may have occurred in the opposite direction.The new specimen also contributes to the renewal of the evolutionary history of pantodonts and provides further insights into the migration and dispersal of Paleocene mammals.
文摘Within the dicynodont genus Turfanodon,there are two recognized species,T.bogdaensis and T.jiufengensis.Both species are known by relatively complete cranial materials,but the mandibles and most postcranial bones have been described only for T.jiufengensis.This paper reports new dicynodont specimens from Turpan,Xinjiang,referring them to T.bogdaensis.They can clearly be differentiated from T.jiufengensis by the flatter lateral surface of the snout region,a prominent swelling on the lateral dentary shelf,and the rounded femoral head.The diagnosis of Turfanodon is revised.The combination of a flat circumorbital rim,posterior portion of anterior pterygoid rami with converging ventral ridges,and a possible autapomorphy,a deep notch on scapula forming procoracoid foramen,are confirmed.It also differentiated from all dicynodonts other than Myosaurus,Kembawacela and Lystrosaurus by having accessory ridges lateral to the median palatal ridge.
文摘The early Silurian Chongqing Lagerstätte(middle Telychian)yields exceptionally preserved articulated jawless and jawed fishes.Here,we describe a new eugaleaspiform(Galeaspida,jawless stem-Gnathostomata),Miaojiaaspis dichotomus gen.et sp.nov.,from the Chongqing Lagerstätte in Xiushan,Chongqing,China.The new form resembles Tujiaaspis vividus in the short medial dorsal canal,and the presence of the branching ends of the lateral transverse canal.They differ in that T.vividus has highly developed subordinate branches of the sensory canals that form a reticulate sensory canal system,and the median dorsal opening is more elongated.Our phylogenetic analysis recovers M.dichotomus and T.vividus as a monophyletic clade(Tujiaaspidae fam.nov.),which is supported by two synapomorphies:the short medial dorsal canal,and the branching ends of the lateral transverse canal.Tujiaaspidae forms a trichotomy with Shuyuidae and a clade comprising Anjiaspis,Sinogaleaspidae,Yongdongaspidae,and the‘eugaleaspid cluster’.The sensory canal patterns in galeaspids are compared to show the transformation sequence of the sensory canal system in Eugaleaspiformes.
文摘X-ray computed tomography(CT)has been an important technology in paleontology for several decades.It helps researchers to acquire detailed anatomical structures of fossils non-destructively.Despite its widespread application,developing an efficient and user-friendly method for segmenting CT data continues to be a formidable challenge in the field.Most CT data segmentation software operates on 2D interfaces,which limits flexibility for real-time adjustments in 3D segmentation.Here,we introduce Curves Mode in Drishti Paint 3.2,an open-source tool for CT data segmentation.Drishti Paint 3.2 allows users to manually or semi-automatically segment the CT data in both 2D and 3D environments,providing a novel solution for revisualizing CT data in paleontological studies.
文摘The Tyrannosauridae,which is characterized by specialized pachydont dentition and putative bone-cracking predatory strategies,is one of the most extensively studied theropod lineages.Although tooth replacement patterns,crucial for understanding feeding behaviors,have been thoroughly studied in this group,studies on non-tyrannosaurid tyrannosauroids are relatively scarce.This study utilizes high-resolution CT data to investigate the tooth replacement pattern in two specimens of Guanlong wucaii,a Late Jurassic tyrannosauroid,and provides insights into the evolution of tooth replacement across Tyrannosauroidea.Second-generation replacement teeth,a rarity observed mainly in giant predatory theropods(e.g.some tyrannosaurids),were detected in the dentary dentition of the juvenile Guanlong.Zahnreihen reconstructions display a consistent cephalad alternating tooth replacement pattern in the maxilla and the dentary of both of the examined individuals,with Z-spacing values exceeding 2.0.As Guanlong grows,the Z-spacing value in the maxillary dentition increases,resembling the ontogenetic changes documented in the Tyrannosauridae.Additionally,like Tarbosaurus,Guanlong also displays a discontinuity between the tooth replacement waves at the premaxilla-maxilla boundary.This study thus demonstrates that some tyrannosaurid-like tooth replacement patterns were acquired before the origin of the Tyrannosauridae.
文摘A relatively well-preserved rodent fossil,including its incisors,cheek teeth,and postcranial skeleton,was collected from the Baiyin Obo in Siziwang Banner,Nei Mongol.A multifaceted research approach was undertaken in this study to conduct a comprehensive analysis on the newly discovered specimen.Based on a morphological comparison,the new specimen was identified as Hulgana cf.H.ertnia within the Ischyromyidae family.Incisive enamel microstructure analysis revealed the typical pauciserial enamel structure of Hulgana.Bone histological analysis indicates that the specimen represents a juvenile individual,which is consistent with the ontogenetic stage indicated by dental developmental stage and wear pattern.The application of geometric morphometrics to the calcaneus and bone histology of the femur and phalanx further substantiates the taxonomic classification of Hulgana as a terrestrial and cursorial rodent,exhibiting a degree of fossorial ability.This classification is analogous to that of certain extant cricetids and ground squirrels.
